The present invention is directed to a longitudinal split sleeve having a strip-like sleeve member composed of a thermo-plastic synthetic member having a shape memory. The sleeve member has longitudinal edges and closure means for closing the edges together so that the edges can be sealed together after the sleeve has been wrapped around an object and the sleeve is shrinkable onto the enclosed object when heat is applied. The closure arrangement includes a plurality of radially extending elements along one edge of the sleeve member which are received in apertures disposed in space relationship along the other edge and at least one of the two edges is provided with a reinforcing member or reinforcement.
A longitudinally split sleeve which consists of a thermo-plastic synthetic material which is capable of a shape memory is discussed in copending U.S. patent application Ser. No. 313,342 filed Oct. 20, 1981, which was based on German patent application No. P30 48 051.4 and the disclosure of this application is incorporated by reference thereto. As disclosed in this application, the sleeve is closed by having its longitudinal edges arranged in overlapping relationship and each longitudinal edge is provided with a closing element which will mutually engage one another. These closing elements are designed as hook elements provided in one reinforcing member secured to one edge of the sleeve and apertures formed in the other reinforcing member secured to the other edge of the sleeve member. The reinforcing elements or members are more thermally stable than the material of the sleeve and therefore hardly change during the shrinking operation. However, the manufacture of this split sleeve to attach the separate closing elements requires a manufacturing process, which must utilize a plurality of steps.
A heat shrinkable, split sleeve consisting of a synthetic which exhibits a closing means consisting of two parts loosely engaged in one another is disclosed in German OS No. 2652014. One part of the closing device consists of metal fingers which are formed to engage the other part and prevent a disengagement of the two edges. The sleeve however, has the disadvantage that the projecting metal fingers will be deformed as a result of the radially influencing shrinking forces and finally release one another when no additional measures are undertaken.